New package: XCFun (#15199)

var/spack/repos/builtin/packages/xcfun/package.py

+# Copyright 2013-2020 Lawrence Livermore National Security, LLC and other
+# Spack Project Developers. See the top-level COPYRIGHT file for details.
+#
+# SPDX-License-Identifier: (Apache-2.0 OR MIT)
+
+from spack import *
+
+
+class Xcfun(CMakePackage):
+    """Exchange-Correlation functionals with arbitrary order derivatives."""
+
+    homepage = "https://github.com/dftlibs/xcfun"
+    url = "https://github.com/dftlibs/xcfun/archive/v2.0.0a4.tar.gz"
+
+    maintainers = ['robertodr', 'bast']
+
+    version('2.0.0a6',
+            sha256='a51086490890393439f98c5e3e4e1622908fe934bbc5063b1d4363cc4c15496d')
+
+    extends('python')
+    depends_on('cmake@3.11:', type='build')
+    depends_on('python@3:')
+    depends_on('py-pybind11')
+    depends_on('py-numpy')
+
+    def cmake_args(self):
+        spec = self.spec
+
+        args = [
+            "-DCMAKE_INSTALL_LIBDIR=lib",
+            "-DPYMOD_INSTALL_LIBDIR=/python{0}/site-packages".format(
+                spec["python"].version[:-1]),
+            "-DXCFUN_MAX_ORDER=8",
+            "-DXCFUN_PYTHON_INTERFACE=ON",
+            "-DPYTHON_EXECUTABLE={0}".format(spec['python'].command),
+        ]
+        return args